Treatment of cast-iron particles and articles made therefrom



Dec. 26, 1922. 1,439,907.

W. C. MAIN. TREATMENT OF CAST IRON PARTICLES AND CLES MADE THEREFROM.

FILED NOV=17|19 awuemboz %/r (7%02 m wa Patented Dec. .26, 19.22.

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W LTER 0. MAIN, or LAKnWoon-orrrc;

riser 'rnna'rmnn'r or cas'r-Inoiv ranrrcnns Ann narrows Mann rr-rnnnrnonr.

Application filed November 17, 1920. Serial No. 424,628.

To all whom itmay concern:

Be it known that I. W'ALTERC. MAIN, a citizen of the United States, and a resident of Lakewood," county of Cuyahoga, and State of @hio, have invented a new anduseful Improvement in the Treatment of Castlron Particles and Articles Made There from, of which the following is a specifica tion, the principle of the invention being herein explained and the best mode in which I have contemplated applying that principle so as to distinguish it from other inventions.

The invention herein relates to articles formed from'cast iron: particles and the treatment thereof before or after their formation into briquettes or other articles so that the finished product will retain its shape. This treatment is particularly useful. in connection with briquettes used as material for furnace charging and has in view the production of an article which may withstand the frequent handling necessary in such use, Without fracturing or being. re

duced to powder through abrasive action 1 during. shipment or transfer.

I have found thatwhen briquettes are made of steel particles such as borings, turnings and thelike, or of such particles of other metals, such as brass, copper and the like, no difiiculty is experienced in forming the same into briquettes'which will successfully withstand hard usage. However, when particles of this character of cast iron are used for the briquette. material, it is found that they readily fracture, and can- .not be handled est care. i a

The object of my invention is to so treat the material out of which briquettes are formed or the briquettes themselves after being formed of cast iron particles asto make the finished briquettes of an extremely durable character, and equalfor the purpose or shipped without the great in view to the briquettes manufactured of the other materials mentioned.

While I have particularly mentioned briquettes I do not mean to limit the application of my invention to any desired form of the finished article, whether in the shape of rods, balls or any irregular form determined upon. To the accomplishment of the foregoing and related ends, said invention, then, consists of the method hereinafter fully described in the claims.

In saidannexed drawing r Fig. l is a perspective view, of a bri of cylindrical shape to be treated by my method; Fig. 2-is a cross-section of a briquette, showing the change in the SUPQI:

and particularly pointed out que tte ficial character thereof produced through i to this highly compacted surface.

.After the briquettes are formed in the compressing apparatus of any preferred design, I subject them for a period of approximately five minutes to a bath of hydrochloric acid preferably of a strength of from three to five per cent. This I find produces a very tenacious superficial coating upon the briquette, which enables it to withstaiul any amount of handling in ordinary course of industry. Instead hf treating the briqnette after its formation in a press, linay treat the borings or other "particles for a like period immediately prior to their compres- A difference is noted in the cohesive characteristics ofthe briquettes treated in each of these two manners, a greater degree of tenacity being exhibited by the briquettes formed ofborings which receive preliminary sion.

treatment.

more particularly change =produced Physical tests.

Straight compression:

As formed Treated briquette Treated borings lbs.

the use of my method of treatment; Fig. 3 is a perspective view of a form of briquette to which my treatment is particularly applicable,the ends of said briquette having: domeshaped portions of low elevation; and Fig. l: is a cross-sectional view of the form illustrated in Fig. 3, showing the greater density" of the outer portions of said briquette, and the results of the application of my treatment means of the drop test it yvill benoted the treated briquette is four tunes as tenacious as the ordinary briquette after-a period of.

l l v 1,439,907

Drop test (15 feet on concrete).

It will be noted that the treated briquette,

Whcthersuch treatment is of-the finished briquette or of the borin-gs, exhibits a considerably greater resistance to compressionthan the briquette not so, treated. This power of resistance increases after an inter-val of about tiventy=four1hoursI By six hours has elapsed, and eight times as tenacious after twenty-four fhours has elapsed. The treated borings' more' -ahan double the 'resisting power of thebriquette after the lapseot twenty-four" hours from that exhibited after a period of six hours.

The treatment is also of advantage inreducing the sulphur content'of thebriquettes, the. preliminary treatment of the 'b'orings in this respect showing a less amount of sulphur than the briquettes treated after compression, but" a greater percentage of oxide thanthe briquettes sotreated.

I also find that the. useof hydrochloric acid of the strength indicated produces a very rapid change in the material and: no

unfavorable incidental effects are noted such assecondary reactions or hygroscopic phenomena. The acid acts at once to produce the cohesive coating to a certain degree and with a shallow depth cit-penetration. 'Substantially the maximum degree of tenacity is attained after the 'elapsingof the tWent-yfour hour-period, but Where the borings or particles are treated prior to compression, such treatment must be immediately 'followed by the molding and compressingop eration to insure the most effective results.

.As a further development of my invention. I may combine the steps above. outlined and after compressing a briquette from the treated borings gi'vexa further treatment tothe finished briquette With hy i drochloric acid of the strength indicated for a slightly longer. period or-usejacid of a slightly greatertconcentration, thus produc-. ingan outside area of greater depth of pene s tration than would be furnished by the acid applied directly to the particles and insure a uniform coating of oxide upon the outside surface of the briquette.

Other steps or forms maybe employed embodying the features of my invention instead .of the ones hereinexplained, change being made inthe steps or forms, provided those stated'by any of the following claims or the equivale-nt'thereof be employed.

I therefore particularly point out and distinctly claim as myinventionz-- 1. A. briquette formed of cast iron particles having an" iron oxideexteriorcoating of uniform distribution, and highly cohesive character, and of merely superficial peneg tration, produced by treatment with hydrochloric ac1d.

2Abriquette of castiron particleshaving a. compressed central portion and a more highly compressed portion adjacentits 'sur-. faceythe lastnamed portion having a superficial coa-ting of smallpenetration to give to; i the brlquette a cohesive'tenacious exterior to permit handling and shipping 3. The method of producing a non: frangible article of cast'iron particles which. comprises'treating such particles with hydrochloric acid to rapidlyoxidize the same,

to'make them cohesive when formed'into finished products.

4. An article of compressed cast iron particles havin homogeneous central portion ot' medium compressed character, an

exterior portion of substantial depth of highly compressed character, and: a; superiicial portion of lesser ,depththan the last 'DlGDtlOHQCl portion ;of 1 .'lllgl1ly cohesive character and 1nod1fiedform of the original substance. r

5. The method of, preparingcast iron.

particles for manufacture into non-frangible briquettes, Which comprises" the treatment thereafter immediately compressing the same.

6. The

pressing apparatus," which. consists in subecting said particles for hunted time to the action of hydrochloric acid to accelerate oxidation thereof, substantially as described.

7. The method of preparing cast iron:

particles for manufacture into non-frangible briquettes,- which comprises the treatment of such particles with hydrochloricacid and method of preparing cast iron particles for use in a ll'lOldlIlg and coinof such particles with hydrochloric acid,

thereafter immediately "compressing the same, and then subjecting t 1e finished briquette to a slightly greater degree of action by such acid.

T R 0. MAIN.

Signed-by me, this 12th day of ll'ovember; 1920. 

